Audio systems are very sophisticated devices used in many applications. Clarity and lucidity of modern audio systems have advanced tremendously. Despite the advances, however, the present systems do not adequately compensate or account for ambient conditions of the surroundings in which the systems are used.
An example of an audio system is a car stereo. The car stereo is located inside a car and, therefore, must interact with a wide variety of ambient noises. In a typical scenario, when the car is initially started, the ambient noise level due to road noise, wind noise, and engine noise is relatively low. Therefore, the car stereo may be set at an initial, low volume level. As the car begins to move, however, the ambient noise level increases, so the volume level of the car stereo must also increase to compensate for the increased noise. When the car reaches a high speed, the ambient noise becomes very loud so that the volume level of the car stereo must be increased even more. If the car slows, the ambient noise decreases and stereo volume level must be manually reduced. As a result, the volume level of the car stereo must be adjusted a number of times during a drive, so that the stereo can be heard comfortably over the varying ambient noise.
This constant requirement of adjusting the car stereo volume is undesirable for several reasons. Most importantly, for a driver to adjust the car stereo volume, he must remove his concentration from the road, thereby putting himself and others at risk. Furthermore, the constant adjustment of the car stereo volume can be a nuisance to the listener and detracts from the enjoyment of listening to the car stereo.
Therefore, what is needed is a system and method for automatically adjusting the volume of an audio system to compensate for variations in ambient noise.